학술논문

Distance and Velocity Characterizations Through Sampling Rate-Limited Main Interferometer in a Silicon Platform
Document Type
Periodical
Source
IEEE Photonics Journal IEEE Photonics J. Photonics Journal, IEEE. 16(3):1-6 Jun, 2024
Subject
Engineered Materials, Dielectrics and Plasmas
Photonics and Electrooptics
Optical interferometry
Optical imaging
Laser radar
Distance measurement
Frequency modulation
Gratings
Transforms
FMCW
LiDAR
resampling
Hilbert transform
auxiliary interferometer
main interferometer
Language
ISSN
1943-0655
1943-0647
Abstract
The Hilbert transform can resample the signal to compensate for the nonlinear frequency sweeping phenomenon and precisely measure a distance and velocity through frequency-modulated continuous-wave (FMCW). Instead of an additional auxiliary interferometer, the direct Hilbert-transform resampling on the main interferograms of a silicon platform could correct the optical-source phase error to form compact light detection and ranging (LiDAR) systems in the characterizations of distances and velocities. More than two samples in an interferogram period will be a criterion in the sampling rate-limited FMCW distance tests. 876.86 cm and 18.058 cm ranging limits are demonstrated through 5 × 10 5 and 1x10 4 samples per second from the data acquisition, respectively, in a process-insensitive Mach-Zehnder directional coupler for FMCW-based LiDAR applications. The velocity of 200 mm per second was also illustrated in 5 × 10 5 samples per second. Moreover, the Hilbert-transform resampled on the main interferometer is superior to the peak-valley approach in the resampling data points, ranging accuracy, and low noise.